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Comprehensive study of the microscopic material removal mechanism remains an open challenge facing the robotic belt grinding of complex geometries. In the present paper, a new material removal rate (MRR) model is developed underlying the motion trajectory of single spherical abrasive grain by taking into consideration the elastic deformation of the heterogeneous contact wheel. In this model, the contact pressure distribution at the contact wheel–workpiece interface is determined by converting the three-dimensional contact problem into a one-dimensional linear spring model with respect to the large deformation of the contact wheel. In addition, the combined modulus and Poisson's ratio of the heterogeneous contact wheel are further considered based on the geometric relation of the Young's modulus and Poisson's ratio. Compared with the existing MRR model, the proposed MRR model can significantly reduce both the root mean square error (RMSE) and mean absolute percentage error (MAPE) values from 2.401 to 1.725, and 18.426% to 14.942%, respectively. Particularly, an optimization strategy from the perspective of process parameters is implemented to balance the grinding quality and efficiency.

This work is motivated by the fact that one key parameter of r 0, which is defined as the effective contact radius of grain, in grinding temperature calculation model (TCM) proposed by Marinescu et al. is usually assumed as a constant in the range of 5–20 μm in different grinding conditions, and this assumption often leads to poor prediction accuracy and limits the widespread application of this model. In this paper, an improved temperature calculation model (I-TCM) considering the grain geometry and distribution is proposed to further optimize the grinding temperature. In this new model, the convection heat transfer coefficient (h f ) is modified considering the cone angle (θ), grain size (g), and grain concentration (V g) effects, and the “workpiece-wheel” partition ratio (R ws) is improved considering the cone angle effect. Theoretical analysis and experiments are carried out for verification in details. The results show that the I-TCM gives the better match with the experimental results than the existing TCM, in which the R ws values characterized by the cone angle and effective contact radius of grain are more sensitive to the grinding temperature than the convection heat transfer coefficient. Furthermore, the effects by the grain size and grain concentration on the grinding temperature could be negligible for the simplification of the calculation process. The I-TCM given in this paper is helpful to the optimization and control of temperature in a practical grinding process.